My Roubaix Pro had the Specialized seatpost. I had to replace it. Despite using a torque wrench at the proper setting the post was damaged by an off-set seatpost clamp, making it unsafe to ride. I later came to learn that the carbon in the Specialized post is especially thin. I've got over 300 miles on a new alum Bontrager seatpost with a single allen wrench adjustment. I notice absolutely no difference between the ride of the old carbon and the new alum posts. Lowering you tire pressure by five lbs is likely to make more of a difference than the seatpost.

Disclaimer: This is just my experience. The experience of others may vary, as I suspect you'll find quickly enough.